U.S. Pat. No. 6,213,538 relates to an armrest and method for manufacturing the same. The '538 patent discloses an armrest bun comprising a die-cut foam pad adhered to a plastic substrate. The substrate and foam are inserted within the armrest skin to provide cushioning for the occupants of a vehicle.
Armrests are manufactured in many and various sizes and shapes for all sorts of transportation vehicles as well as for furniture. In the past, armrests were generally rectangular in shape to simplify manufacturing. The trend in newer vehicles now includes complex curvatures and tapered surfaces. This new more curved shaping may be more aesthetically appealing and may provide better comfort by conforming more closely to the shape of the portion of the arm that may be cushioned.
The foam comprising the armrest bun may closely match the outer shape of the armrest and fully support the outer skin so that wrinkles and depressions are not seen.
A problem relates to the shaping of the die-cut foam, such as disclosed by the '538 patent, to properly fit the more curved armrests of today. Providing a die-cut foam bun having the desired shaping, which may include complex curvatures and tapered surfaces, may require a number of cutting operations. Multiple workstations may be required to focus on the cutting of the different and varied surfaces. For instance, one station may be needed to cut a blank, another station may be needed to cut a curve on the blank, and yet another station may be needed to cut a taper on the blank, all in a less than desirable cost effective manner.
Armrests were manufactured as a separate component for many years, and comprised a formed metal or plastic substrate, a separately molded outer skin and urethane foam precursors poured between the skin and substrate which expanded and cured to form a semi-rigid cushioning foam. This component was then mechanically attached to, for instance, the inner door panel of a vehicle.
More recently, a more efficient manufacturing process has been developed wherein the outer skin and substrate may both be injection molded by “insert-molding” or “over-molding” such that a pocket or cavity is created, into which a foam bun may be inserted to form the armrest.
U.S. Pat. No. 7,055,888, commonly owned by the assignee of the present disclosure is directed at a skin coupled to a first substrate that forms a cavity for inserting a foam bun into, the bun comprising a second substrate and a foam layer bonded to the second substrate. The first and second substrates are connectable to position the armrest on a door panel.
The present disclosure provides a less complex, more cost effective assembly by eliminating the second substrate or replacing the second substrate with a second relatively harder foam that may be formed coincident with the relatively softer foam bun. Accordingly, a more cost-effective method for manufacturing insertable armrest buns is provided.